Matrix converter motor winding temperature control with closed feedback loop

A method to provide alternating current (AC) voltage and direct current (DC) to a multi-phase motor having motor windings, the method comprising:

• receiving, at a signal processor or processing module of a matrix converter, signaling from a motor winding temperature sensor, wherein the signaling includes information about a temperature of at least one motor winding of the motor windings that is sensed inside the motor by the motor winding temperature sensor when the motor is not being required to produce torque and rotation;
• receiving signaling from an ambient temperature sensor located externally to the motor, wherein the signaling from the ambient temperature sensor includes information about an ambient temperature outside of the motor;
• determining an alternating current (AC) voltage to provide sufficient power to produce torque and rotation in the motor;
• based on the received signaling that includes information about the temperature of the at least one winding and about the ambient temperature, determining a pulsating direct current (DC) voltage to provide sufficient average power to generate a level of heating, sufficient to prevent or reduce moisture in the motor, when the pulsating DC voltage is applied to the at least one motor winding of the motor, wherein the average power of the pulsating DC voltage is lower than the power of the AC voltage so as not to produce torque and rotation;
• using a proportional/integral/derivative (PID) algorithm to activate a motor heat mode;
• and
• applying the pulsating DC voltage to the at least one winding during the motor heat mode, wherein:
• the pulsating DC voltage comprises a DC waveform having a a plurality of DC pulses in each cycle of the DC waveform,
• the pulsating DC voltage is applied to heat the at least one winding to within a first temperature range above the ambient temperature, if the ambient temperature is within a second temperature range,
• the pulsating DC voltage is applied to heat the at least one winding to maintain a continuous winding temperature, if the ambient temperature falls below a first threshold temperature, and
• application of the pulsating DC voltage is stopped, if the ambient temperature rises above a second threshold temperature.

An apparatus to provide alternating current (AC) voltage and direct current (DC) to a multi-phase motor having motor windings, the apparatus comprising:

• a motor winding temperature sensor coupled to the motor windings;
• an ambient temperature sensor;
• and
• a matrix converter coupled to the motor winding temperature sensor and to the ambient temperature sensor, wherein the matrix converter includes a signal processor or processing module configured to:
• receive signaling from the motor winding temperature sensor, wherein the signaling includes information about a temperature of at least one motor winding of the motor windings that is sensed inside the motor by the motor winding temperature sensor when the motor is not being required to produce torque and rotation;
• receive signaling from the ambient temperature sensor located externally to the motor, wherein the signaling from the ambient temperature sensor includes information about an ambient temperature outside of the motor;
• determine an alternating current (AC) voltage to provide sufficient power to produce torque and rotation in the motor;
• based on the received signaling that includes information about the temperature of the at least one winding and about the ambient temperature, determine a pulsating direct current (DC) voltage to provide sufficient average power to generate a level of heating, sufficient to prevent or reduce moisture in the motor, when the pulsating DC voltage is applied to the at least one motor winding of the motor, wherein the average power of the pulsating DC voltage is lower than the power of the AC voltage so as not to produce torque and rotation;
• use a proportional/integral/derivative (PID) algorithm to activate a motor heat mode;
• and
• apply the pulsating DC voltage to the at least one winding during the motor heat mode, wherein, the pulsating DC voltage comprises a DC waveform having a high frequency transistor switching component riding on the DC waveform and further having a plurality of DC pulses in each cycle of the DC waveform.